Railway traffic controlling system



Oct. 2, 1934. w, K HOWE RAILWAY TRAFFIC CONTROLLING' SYSTEM Filed Dec. 19, 1931 y ,GMM

INVENToR w75@ /J ATroRN'EY Patented Oct. 2, 1934 PATENT OFFICE 1,975,135 RAILWAY TRAFFIC CONTROLLING SYSTEM Winthrop. K. Howe, Rochester, N.

General Railway Signal Company,

Y., assigner to Rochester,

ApplicationDecember `19, 1931, Serial No. 582,108V 9 Claims. (Cl. 246-3);

ever, the contact 6 is preferably held, irrespec- This invention relates to traffic controlling systems for railroads, and more particularly pertains to the remote control of power operated track switches.

The present invention contemplatesv a control system for power operated track switches in which the operation of a track switch is prevented from being initiated during the occupied condition of an associated detector tracksection; and also in which an operation of the trackrswitch already initiated is caused to be completed upon the entrance of a train into the associated detector track section, which is generally more desirable in such cases, than causing a switch to be stopped in midstrokav l Variousrother features, advantages, and characteristic functions of the present invention will be in part pointed out, and in part obvious from the accompanying drawing, as the description progresses. v

-In describing the invention in detail, reference will be made to the accompanying drawingwhich illustrates inV a simplified and diagrammatic manner the circuits andparts of a switch machine control system embodying the present invention.

With reference to the accompanying drawing, a railroad track switch TS isindicated as bei-ng operated by a swith'machineSMof any suitable type, such for example, as disclosedin my Patent No. 1,466,903, dated Septemberv 1,l 1923. This switch machine has associated therewith a control relay CR together with normal and reverse contactors N and R orgoverning the normal and reverse operating circuits of the usual armature -Afand eld winding These relays ymay be located within the switch machine structure or may be suitably provided withv a separate housing, as desired. Also, inasmuch as Vthese relays open and close the operating circuits of lthe switch machine motor, the .usual pole changer contacts and pole changer coilsare omitted. `The rswitch machine SM is provide-d, however, with suitable point detector contacts and associated mechanism, as shown for example in the patent to C. S, Bushnell Patent No. 1,517,236, dated November 25, 1924,- which mechanismincludes two pair of Xed contacts 2 and 3 together with movable contacts 4 and 5. The movable contacts 4 and 5 are jointly operated by thetrackswitch TS and the switch machine SM so-as to assume normal or reverse positions when thetrack switch TS is in normal or reverse extreme locked positions respectively, and so as to assume intermediate midstroke positionswhenever the track switch TS is being operated by the switchmachine SM or whenever the track switch TS-y is unlocked.

The control relay CR is preferably of the polarized type having its contact 6 operated to opposite extreme positions upon the application of potential of opposite polarities to is windings'. Howtive of continual energization of the relay, in itsA last operated position by either a magnetic stick structure or a suitable mechanical toggle arrangement.

The normal andreverse contactors N and Rare of the neutral marginal type, thatis, when their operating windings 7 and 8 respectivelyfare energized at the same time that their holding windings 9 and; 10 respectively are energized, thei r contacts will be picked up, but if only the holding windings are energized their contacts will not pick up.. Also, if the contacts of thesecontactors are. once picked up and only the holding windings are, energized, then the'contacts will remain in picked up positions. v

Associated with the track switchv 'ISjis.` the usual detector track section having a trackbatf tery and the, usual track relay T. It is also to b e understood, that there are suitablel signals (not shown) associatedwith the trackA switch TS for governing traic thereover in accordance with standard practice. f f

.The control relay CR isv operated in accordance withthe ,manualactuation of a switch machine controllever SML, located in the tower, over a 'suitable polarized line circuit. The switch machine lever SML maybe of any suitable type, that is, it may be a free lever as illustrated with suitable'electric interlocking associating it with the remainder ofV the system, or it may be the usual mechanically interlocked lever having associated therewith suitable detector locking and the like, as disclosed foi-example in my Patent No. 1,550,611, dated August 18, 1925. Suitableapproach locking means may also be incorporated when desired. Y

vA battery BT has been illustrated as supplying the power for the controland operatingcircuits over bus wires 12 and 14, it being understood of course thatany other suitablesource may be employed. The bus wires 12 and 14 are considered as extending from thetower, or powerhouse to all ofthe outlying switch machinesl It is believed that the nature of the invention, its advantages and characteristic features can be best understood with further description being setforth from the standpoint of operation.

' Operation With the control lever SML in its present normal position, the control relay CR is energized by a circuit from the positive bus 12, through wires 20 and 21, contacty 22 of lever SML in a nor-A mal positiomwire 23, windings of relay CR, wire 24, contact 25 of lever SML in a normal position, wire `26, to the negative bus 14. Assuming vtraliic conditions 'are such as to properly condition the associated interlocking means (not shown-either electric or mechanical) and that the detector track section associated with the track switch TS is unoccupied, track relay T is therefore energized. Under these conditions, if the operator moves the switch machine lever SML to the opposite position, the polarity is reversed on the control relay CR thereby actuating polar contact 6 to its opposite position. For example, the movement of contacts 22 and 25 to reverse positions causes a reversal of current by completing a circuit from the positive bus 12, through Wires 20 and 27, contact 25 of lever SML in a reverse position, wire 24, windings of relay CR, wire 23, contact 22 of lever SML in a reverse position, wire 26, to the negative bus 14.

The contact 6 of relay CR in a right hand p0- sition completes a pick-up circuit for the reverse contacter R from the positive bus 12, through wires 28 and 29, contact 6 of relay CR in a right hand position, wire 30, point detector contacts 2 4, wire 3l, pick-up winding 8 of reverse contactor R, wires 32 and 33, front contact 34 of track relay T, wire 35, to the negative bus 14. At the same time that the pick-up winding 8 is energized, the holding Winding l0 is energized through a circuit from the positive bus l2, through wires 28 and 29, polar contact 6 of relay CR in a right hand position, wire 30, point detector contacts 2 4, wire 31, .holding winding 10 of reverse contactor R, wire 36, to the negative bus 14. Y With both the pick-up and holding windings energized, the degree of energization of the reverse contactor R is sufficient to cause the contact .37 to be actuated to a picked up position, inwhich position it closesthe reverse operating circuit for the switch machine. In other words, the energization of the reverse contacter R causes the motor ofthe switch machine to be operated in a reverse direction by closing a circuit from the positive bus 12, through wires 28, 38 and 39, front contact 37 of reverse` contactor R, eld winding F, back contact 4G of normal contactor N, wire 41, armature A,'wire 42, to the negative bus 14. This circuit causes the reverse operation of the switch machine, but during this operation the switch machine cannot be stopped in mid stroke upon the detector track section becoming occupied by opening the pick-up circuit for the reverse contacter R at open front contact 34, as the current ow in the holding winding 10 `is sufficient to hold contact 37 in alpicked up or energized position.

As soon as the switch machine SM has unlocked the track switch TS, the movable contacts 4 and 5 are operated to intermediate or mid stroke positions in which the contacts 3 5 are made'. Thus, during such mid stroke conditions, if the contact 6 is returned to a normal position as a result of the return of lever SML to a normal position, the reverse contactor R will be deenergized closing back Contact 37 and the normal contactor N will be energized, closing its front contact 40, thereby reversing the operation of the switch machines. This assumes of course that the detector track section is not occupied, and that the operation of the lever SML must be governed in accordance with the usual interlocking associated therewith, the usual approach locking, detector locking and the like, in accordance with the usual signalling practices.

Y However, assuming that the switch machine continues the reverse operation, at the end of the loperating stroke after the track switch TS has assumed its reverse locked position, the contacts 4 and 5 are operated to their reverse extreme positions. The opening of contacts 2 4, opens the energizing circuits for both the pick-up and holding windings 8 and 10 thereby allowing the contactor R to be deenergized for closing back con- `tact 37 deenergizing the motor armature A and field winding F; while the continued closure of contacts 3 5 maintains the system in a condition permitting the normal operation of the track switch.

It is believed that the opposite operation Will be readily understood by analogy to the operation already described, as such operation is merely the converse of that already described.

Whenever the detector track section associated with the track switch TS is occupied, the track relay T is deenergized thereby preventing the initiation of a new operation. For example, assuming the track switch to be in a normal position and the track relay T to be deenergized when the operator moves the control l ver SML to a reverse position, the control relay responds as usual by operating the polar contact 6 to a right hand position, thereby closing the holding circuit for the reverse contactor R butr the usual circuit for the pick-up winding 8 is opened at open front contact 34, which prevents the response of the reverse contactor R. It is to be noted, however, that a circuit is completed 'from the positive bus 12 through wires 28 and 29, polar contact 6 of relay CR in a right hand position, wire 30,Y

point detector contacts 2 4, wire 31, pick-'up winding 8, wires 32 and 43, pick-up winding 7 of normal contacter iN', holding winding 9 of. normal contactor N, wire 44, to the negative bus 14. As this circuit includes three windings in series, the resistance of the circuit is suinciently high to limit the current flow in the pick-up winding 8 of the reverse contacter R to a value below that which will cause the actuation of contact 37to an energized position. Also, as the current flows differentially in the windings 7 and 9 of the normal contactor N, and as the current is of Very low value, the contacts of this contactor like'- wise remain in retracted positions.

Thus, when the track relay T is deenergized and front contact 34 is open, the contactors N and R are energized only to a very low degree, which degree of energization is below that which is required to actuate their contacts to energized positions.

The normal and reverse contactors N and R preferably have associated therewith suitable .magnetic blow-out means so that the arcs created at front contacts 37 and 40 will be readily extinguished. Also, these contactors preferably have associated therewith suitable overload protective means together with means for causing the interruption of either the normal or the reverse contactor pick-up and holding circuits upon the occurrence of such an overload so as to prevent the continual operation of the switch machine motor, but which means still permits the operator to govern the switch machine so as to return the track switch to its former position, all of which has been more completely disclosed and described in the patent to Hoppe and Swanton, Pat. No. 1,877,876, dated September 20, 1932.

Summary. Thus, a remote control circuit for switch machines has been disclosed in which the power is transmitted directly to the switch machines where it is applied locally to their operating circuits in accordance with remote manual control and in accordance `with adequate detector locking means local thereto. The remote manual ico control is effectedover polarized circuits governed by manually operable leversrand repeated by two position polar relays; while the detector locking is accomplished by the use of marginal type contactors or relays for governing the operating circuits of the respective switch machines, which contactors are controlled by their respective polar `relays and their respective detector track sections. A system, thusl organized in accordance with the present invention,l provides reversibility oi Va track switch in mid-stroke, prevents initiation of ythe track switch during the occupied condition of the associated detector track section, and permits thecompletion of an operation already initiated upon the detector track section becoming occupied. v

Having described a switch machine control system as one specific embodiment of the present invention, it is desired to be understood that'this form is selected to facilitate in the disclosure of the invention rather than to'limit the number of forms which it may assume; and, it is to be further understood f that various modifications, adaptations and alterations may be applied to the specific formv shown to meet the requirements y'of practicefwithout in any manner departing from the spirit or scope of the present invention except as limited by the appended claims.

What I claim is 1. In combination; a railroad track switch; a detector track section associated with said track switch; a switch machine having a motor for operating said track switch; normal and reverse contactors each having a pick-up winding and a holding winding said contactors respectively governing the normal and reverse operation of said motor; and means manually operable for energizing said holding winding of either said normal contactor or said reverse contactor independently of the condition of the pick-up windings, and for effectively energizing said pick-up winding of either said normal contactor or said reverse contactor only when said detector track section is unoccupied.

2. In a control system for railroad track switches, a switch machine for operating a track switch, point detector contacts having'normal reverse and mid stroke positions, normal and reverse contactors each having pick-up and holding windings and each being actuated only when both of its windings are energized, a detector track section having a track relay associated with said track switch, a control relay having a polar contact operable to opposite extreme positions, means for manually governing said control relay, an energizing circuit for the holding winding of said normal contactor closed when said polar contact is in a position out of corre spondence with said point detector contacts namely in reverse or mid stroke positions, an energizing circuit for the pick-up winding of said normal contactor closed only if said track relay is energized and when said polar contact is in a position out of correspondence with said point detector contacts namely in reverse and mid stroke positions, an energizing circuit for the holding winding of said reverse contactor closed when said polar contact is in a position out of correspondence with said point detector contacts namely in normal or mid stroke positions, an energizing circuit for the pick-up winding of said reverse contactor closed only if said track relay is energized when said polar contact is in a position out of correspondence with said point detector contacts namely in normal and and holding windings both of which must be s energized to actuate said contactor but the holding winding of which need only be energized to maintain 'said contactor actuated, a track relay associated with said track switch for indicating train presence', means for closing an energizing circuit for said pick-up winding only when said trackl relay indicates the absence of trains, and means for closing an energizing circuit for said holding winding independentlyof said track relay, whereby said marginal contactor is eifec- Y tively'actuated only when both of its windings are energized, 'and' whereby said marginal contactor is maintained actuated if only its holding winding is' energized.

4. In a trafc controlling system for railroads, a track switch, a switch machine for operating said trackswitch and having operating circuits, a marginal contactor-forV governing said operating circuits, said contactor having pick-up and holding windings both of which must be energized in order to actuate said contactor, a track relay associated with said track switch for indicating train presence adjacent said track switch, means for closing an energizing circuit for said pick-up winding only when said track relay indicates the absence of all trains and dependent upon the operated condition of said switch machine, and means for closing an energizing circuit for said holding winding independently of said track relay but dependent upon the operated condition of said switch machine, whereby said contactor is actuated only if both of said windings are eiectively energized.

5. In combination; a track switch; a switch machine; point detector contacts jointly operated by said track switch and said switch machine; a detector track section; a manually controlled relay; normal and reverse operating circuits for said switch machine; normal and reverse contactors for closing said normal and reverse operating circuits respectively, said contactors being actuated to picked up positions only with a relatively high flux density but capable of being maintained picked up with a relatively low flux density; pick-up circuit means controlled by said manually controlled relay for selectively setting up said high flux density in said normal and reverse contactors dependent upon said point detector contacts and the unoccupied condition of said detector track section; and holding circuit means for maintaining the actuated normal or reverse contactor picked up by providing a iiuX density of said low value independently of the occupied condition of said detector track section until said switch machine completes its stroke as indicated by said point detector contacts; whereby an operation of said switch machine can be initiated only when said detector track section is unoccupied but which can be completed irrespective of such occupied condition and irrespective of the time required for such completion of the operation.

6. In combination, a distant track switch, a track relay for manifesting the presence of a train near said track switch, a switch machine for operating said track switch, a control relay for controlling said switch machine and having a pick-up circuit and a holding circuit, and a free andynonlockable lever for closing said pick-up circuit for said control relay only when said track relay is energized and for closing said holding circuit of said control relay irrespective of the conditions of said control relay or said track relay, whereby operation of said switch machine may be initiated only when-said track relay is energized but such operation may be discontinued at any time.

y '7. In combination, a distant track switch, a track relay for manifesting the presence of a train near said track switch, a switch machine for oper ating said track switch, a control relay for controlling said switch machine and having a pick-up circuit and a holding circuit, a `free and nonlockable lever for closing said pick-up circuit for said control relay only when said track relay is energized and for closing said holding circuit of said control relay irrespective of the conditions of said control relay or said track relay, whereby operation of said switch machine maybe initiated only when said track relay is energized but such operation Ymay be discontinued at any time, and means for dropping said relay when said switch machine has completed its stroke.

8. In combination, a track switch, a switch machine for operating said track switch, a double winding relay for when energized applying current .to said switch machine, said windings being constructed to cause said relay to assume its attracted position when said windings are energized in mule tiple `and to causeit to remain in its attracted condition if saidV relay has been picked up and said windings are energized in series but to prevent said relay picking up when said windings are energized in series, means for applying current to said windings,and mea-ns for preventing the applica tion of current to said windings in multiple when there is a train approaching said track switch.

9. In combination, a track switch, a switch machine for operating said track switch, two double winding relays either of which when energized applying current to said switch machine, said windings being so organized that when current is applied at one point the windings of one of said relays will be connected directly in multiple and the windings of said other relay will be shunted and when current is applied to another point the windings of said other relay are connected directly in multiple and the windings of said one relay are shunted, and means for preventing the windings of either of said relays to be connected directly in multiple when there is a train approaching said track switch. Y

WINTHROP K. HOWE.

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